The bacteria Staphylococcus saprophyticus is a common cause of urinary tract infections, UTIs, in young women. These bacteria are members of the same genus as Staphylococcus aureus, which is the bacteria responsible for MRSA, methicillin-resistant staph aureus, infections. A patient may confuse the two and worry unnecessarily when she learns that she has a "staph UTI." Although related to Staph aureus, Staph saprophyticus is a distinct species of bacteria and has yet to develop significant antibiotic resistance.
Bactrim
Bactrim is the trade name for a combination of the two sulfa drugs, sulfamethoxazole and trimethoprim. When the two medications are combined, they have a synergistic effect against bacteria. It's a first-line antibiotic for use in staph UTIs because it is inexpensive, is effective against Staph saprophyticus and is excreted in active form in urine. The typical Bactrim regimen for UTIs lasts three days. A seven-day course of treatment is used for diabetics, women over 65 and repeat infections. Common side effects include nausea, vomiting and diarrhea.
Fluoroquinolones
The fluoroquinolone class of antibiotics includes such well-known drugs as ciprofloxacin, or Cipro, and lexofloxacin, or Levaquin. Fluoroquinolones are highly effective against UTIs because, like Bactrim, they are concentrated in the urine. They are effective against a broad range of bacteria, including Staph saprophyticus. Fluoroquinolones are usually not the first choice for a UTI, because this broad spectrum of activity can lead to antibiotic resistance developing in intestinal bacteria, potentially causing a severe form of diarrhea. They are still a good alternative for treating UTIs in patients who are allergic to sulfa drugs, however. Fluoroquinolones rarely cause side effects, with nausea and abdominal discomfort being the most common of those that do occur. Like Bactrim, a standard fluoroquinolone regimen for UTIs lasts three days, with a seven day course being used in some cases.
Non-Drug Treatments
Even without antibiotics, most UTIs will clear up in about a week. Drinking large amounts of fluid can speed this process along, since frequent and plentiful urination helps to flush bacteria out of the bladder. Cranberry juice is a popular folk-remedy for treating UTIs, but rigorous medical evidence supporting its use is scarce. A 2003 Cochrane Library systematic literature review found that while there is some evidence showing cranberry juice to be effective in treating UTIs, all of it is of poor-quality evidence. A 2004 Cochrane review did find that there is some high-quality evidence supporting the use of cranberry juice in preventing UTIs, however.
References
- "Harrison's Principles of Internal Medicine"; Dennis L. Kasper; 2005
- The Cochrane Library: Cranberries for treating urinary tract infections, 2003.
- The Cochrane Library: Cranberries for preventing urinary tract infections, 2004.
